1. Field of the Invention
The present invention generally relates to a portable scanning device and more particularly relates to techniques for providing scanning capability in liquid crystal displays (LCD) devices commonly seen for image or video display.
2. Description of the Related Art
There are many applications that need optical scanners to convert paper-based objects, such as texts and graphics, to an electronic format that can be subsequently analyzed, distributed and archived. One of the most popular optical scanners is a flatbed scanner that converts scanning objects, including pictures and papers, to images that can be used, for example, for designing World Wide Web pages and optical character recognition. Another popular optical scanner is what is called sheet-fed scanners that are small and unobtrusive enough to be carried around, hence referred to as mobile scanners, to provide a handy scanning means.
A mobile scanner comes handy and is often used to convert actual printed or written materials into electronic format. For example, a journalist goes far away from a news bureau to collect information about an important event there. It is considerably useful such a portable or mobile scanner can be used to scan documents on site into a computer that then forwards the electronic versions to the news bureau for immediate news reporting or archival.
Many latest mobile devices are equipped with one or more cameras. For example, iPhones from Apple Inc. are equipped with two cameras, one on the front and the other on the back to allow a user to capture video or images for various purposes. Although the image quality of such cameras is improving over the time, it is difficult to use such cameras to capture documents in good quality. Thus, various scanners are still holding their market shares and being used in applications they have been designed for.
Most current scanners in the market are standalone devices. Some advanced scanners operate on their own while others generally operate with a computer via an interface (e.g., USB). Regardless how a scanner operates, the scanning results are typically stored in a computing or storage device.
On a separate note, flat panel displays or liquid crystal displays (LCD) are possibly the most popular display devices in use today. The decreased weight and size of a flat panel display greatly increases its versatility over a cathode ray tube (CRT) display. They are used in a wide range of applications, including computer monitors, television, instrument panels, aircraft cockpit displays, signage, and etc. They are common in consumer devices such as video players, gaming devices, clocks, watches, calculators, and telephones. LCDs have displaced cathode ray tube (CRT) displays in most applications. They are usually more compact, lightweight, portable, less expensive, more reliable, and easier on the eyes. They are available in a wider range of screen sizes than CRT and plasma displays, and since they do not use phosphors, they cannot suffer image burn-in.
The flat panel LCD units are an excellent display choice for desktop or laptop computers and other portable electronic devices. Some of the LCD devices are equipped with a webcam to allow a user to conduct a video conference with other users online. It is well known that the webcam is not ideal for capturing images of documents. It would be a desirable feature if an LCD flat panel display is equipped with scanning capability for capturing images of documents when there is a need.
Accordingly, one aspect of the present invention is to make it possible that an LCD flat panel display can also provide a scanning function, thus allowing a user to scan a document without using a separate scanner.